1. Field of the Invention
The present invention relates to a water-cooled air conditioner, and more particularly, to a water-cooled air conditioner with a plate type heat exchanger in which refrigerant and cooling water flow against each other, and an anti-freezing device and a flow sensing device for easily assessing freezing and the flow of water.
2. Description of the Related Art
Generally, an air conditioner is a cooling/heating apparatus that cools or heats the air inside an indoor space of an office, home, etc. An air conditioner uses a refrigerant cycle in the sequence of compression-condensation-expansion-evaporation to exchange heat between refrigerant and air to cool or heat air within a specific space.
Recently, air conditioners are being manufactured with not only basic cooling and heating functions, but other functions such as air purifiers that suction and filter contaminated indoor air and discharge clean air, dehumidifiers that convert humid air to dry air and discharge the latter back into an indoor space, and various other functions that ameliorate living.
Also, air conditioners can be divided into split air conditioners that have separate indoor units and outdoor units, and single unit air conditioners that integrate the indoor unit with the outdoor unit. Due to installation space and noise considerations, the split air conditioner is the preferred type today.
Instead of air-cooled air conditioners that use air to exchange heat with refrigerant to condition the air inside an indoor space, increased research and development is being done on water-cooled air conditioners that use water to exchange heat with refrigerant to condition the air inside an indoor space. This water-cooled type of air conditioner is a device that is favored as an alternative to the excessive power consumption of air-cooled air conditioners.
Also, when compared to air-cooled air conditioners, water-cooled air conditioners can be made smaller in size, generate less noise, and condition air more effectively; and due to the increase in the construction of large buildings and complexes such as apartments, the development and production of water-cooled air conditioners is increasing.
However, water-cooled air conditioners according to the related art still have many drawbacks.
For example, in water-cooled air conditioners according to the related art, cooling water and refrigerant are respectively separated while flowing through the inside of a heat exchanger. Thus, the cooling water that flows separately from refrigerant is prone to freeze during winter within the water-cooled air conditioner.
When cooling water freezes within a heat exchanger, the volume of the cooling water expands and damages the heat exchanger. A damaged heat exchanger requires repair expenses.
Furthermore, in a water-cooled air conditioner according to the related art, not being able to check the flowing state of the cooling water is a problem. Accordingly, when the flow of cooling water is restricted by the buildup of impurities in cooling water over prolonged use, the heat exchanger can be damaged.
Additionally, in this type of water-cooled air conditioner according to the related art, because refrigerant and cooling water flow in the same direction during either the cooling or heating cycle, the efficiency of heat exchanging is reduced.